A homogeneous method for investigation of methylation-dependent protein–protein interactions in epigenetics

Methylation of lysine residues on the tails of histone proteins is a major determinant of the transcription state of associated DNA coding regions. The interplay among methylation states and other histone modifications to direct transcriptional outcome is referred to as the histone code. In addition to histone methyltransferases and demethylases which function to modify the methylation state of lysine sidechains, other proteins recognize specific histone methylation marks essentially serving as code readers. While these interactions are highly specific with respect to site and methylation state of particular lysine residues, they are generally weak and therefore difficult to monitor by traditional assay techniques. Herein, we present the design and implementation of a homogeneous, miniaturizable, and sensitive assay for histone methylation-dependent interactions. We use AlphaScreen, a chemiluminescence-based technique, to monitor the interactions of chromodomains (MPP8, HP1β and CHD1), tudor domains (JMJD2A) and plant homeodomains (RAG2) with their cognate trimethyllysine histone partners. The utility of the method was demonstrated by profiling the binding specificities of chromo- and tudor domains toward several histone marks. The simplicity of design and the sensitive and robust nature of this assay should make it applicable to a range of epigenetic studies, including the search for novel inhibitors of methylation-dependent interactions

Acyl derivatives of p-aminosulfonamides and dapsone as new inhibitors of the arginine methyltransferase hPRMT1

Arginine methylation is an epigenetic modification that receives increasing interest as it plays an important role in several diseases. This is especially true for hormone-dependent cancer, seeing that histone methylation by arginine methyltransferase I (PRMT1) is involved in the activation of sexual hormone receptors. Therefore, PRMT inhibitors are potential drugs and interesting tools for cell biology. A dapsone derivative called allantodapsone previously identified by our group served as a lead structure for inhibitor synthesis. Acylated derivatives of p-aminobenzenesulfonamides and the antilepra drug dapsone were identified as new inhibitors of PRMT1 by in vitro testing. The bis-chloroacetyl amide of dapsone selectively inhibited human PRMT1 in the low micromolar region and was selective for PRMT1 as compared to the arginine methyltransferase CARM1 and the lysine methyltransferase Set7/9. It showed anticancer activity on MCF7a and LNCaP cells and blocked androgen dependent transcription specifically in a reporter gene system. Likewise, a transcriptional block was also demonstrated in LNCaP cells using quantitative RT-PCR on the mRNA of androgen dependent genes

Histone deacetylase inhibitor activity in royal jelly might facilitate caste switching in bees.

Worker and queen bees are genetically indistinguishable. However, queen bees are fertile, larger and have a longer lifespan than their female worker counterparts. Differential feeding of larvae with royal jelly controls this caste switching. There is emerging evidence that the queen-bee phenotype is driven by epigenetic mechanisms. In this study, we show that royal jelly-the secretion produced by the hypopharyngeal and mandibular glands of worker bees-has histone deacetylase inhibitor (HDACi) activity. A fatty acid, (E)-10-hydroxy-2-decenoic acid (10HDA), which accounts for up to 5% of royal jelly, harbours this HDACi activity. Furthermore, 10HDA can reactivate the expression of epigenetically silenced genes in mammalian cells. Thus, the epigenetic regulation of queen-bee development is probably driven, in part, by HDACi activity in royal jelly

Identification of Small-Molecule Enhancers of Arginine Methylation Catalyzed by Coactivator-Associated Arginine Methyltransferase 1

Arginine methylation is a common post-translational modification that is crucial in modulating gene expression at multiple critical levels. The arginine methyltransferases (PRMTs) are envisaged as promising druggable targets but their role in physiological and pathological pathways is far from being clear, due to the limited number of modulators reported to date. In this effort, enzyme activators can be invaluable tools useful as gain-of-function reagents to interrogate the biological roles in cells and in vivo of PRMTs. Yet the identification of such molecules is rarely pursued. Herein we describe a series of aryl ureido acetamido indole carboxylates (dubbed “uracandolates”), able to increase the methylation of histone- (H3) or non-histone (polyadenylate-binding protein 1, PABP1) substrates induced by coactivator-associated arginine methyltransferase 1 (CARM1), both in in vitro and cellular settings. To the best of our knowledge, this is the first report of compounds acting as CARM1 activators

Identification of Small-Molecule Enhancers of Arginine Methylation Catalyzed by Coactivator-Associated Arginine Methyltransferase 1

Arginine methylation is a common post-translational modification that is crucial in modulating gene expression at multiple critical levels. The arginine methyltransferases (PRMTs) are envisaged as promising druggable targets, but their role in physiological and pathological pathways is far from being clear due to the limited number of modulators reported to date. In this effort, enzyme activators can be invaluable tools useful as gain-of-function reagents to interrogate the biological roles in cells and in vivo of PRMTs. Yet the identification of such molecules is rarely pursued. Herein we describe a series of aryl ureido acetamido indole carboxylates (dubbed “uracandolates”), able to increase the methylation of histone (H3) or nonhistone (polyadenylate-binding protein 1, PABP1) substrates induced by coactivator-associated arginine methyltransferase 1 (CARM1), both in in vitro and cellular settings. To the best of our knowledge, this is the first report of compounds acting as CARM1 activators